As this type of apparatus, for example, there has been suggested an apparatus for performing a smoothing process on an electric power deviation, calculated by subtracting an assumed electric power to be inputted to or outputted from the motor from an input/output electric power to be inputted to or outputted from a battery, and for setting an input/output allowable limit on the basis of the electric power deviation and an input/output limit of the battery, in order to suppress charge and discharge by an excess electric power of the battery (refer to a patent document 1).
Alternatively, there has been suggested an apparatus for driving a motor generator to crank the engine when receiving a change request from an electric vehicle (EV) driving mode to a hybrid vehicle (HV) driving mode. Here, in particular, the following is described; namely, a discharge allowable electric power is derived such that a direct current voltage of the battery does not fall below a lower limit voltage and a torque command value is adjusted such that a consumption power of the motor generator does not exceed the discharge allowable electric power. Moreover, it is also described that the lower limit voltage is temporarily increased if an accelerator opening degree reaches a predetermined reference value within a predetermined time after the request to change to the HV driving mode (refer to a patent document 2).